Air standard otto Cycle program
1.
% Inputs
gamma = 1.4;
t3 = 2300;
% state variable
p1 = 101325;
t1 = 500;
% engine geometric parameters
bore = 0.1;
stroke = 0.1;
con_rod = 0.15;
cr = 12;
% swept volume and clearance volume
v_swept = (pi/4)* bore^2 * stroke;
v_clear = v_swept/(cr-1);
v1 = v_swept + v_clear;
v2 = v_clear;
% state variables at point2 | p1v1^gamma = p2v2^gamma = pv^gamma.
p2 = p1*(v1/v2)^gamma ;
% compute the value of t2 by using .
t2 = t1*cr^(gamma-1) ;
constant_k = p1*v1^gamma;
V_compression = engine_otto(bore,stroke,con_rod,cr,180,0);
P_compression = constant_k./(V_compression).^gamma;
% state variables at state point 3
v3 = v2;
% p3v3/t3 = p2v2/t2 | p3=p2*t3/t2
p3 = p2*t3/t2 ;
constant_k = p3 * v3^gamma ;
V_expansion = engine_otto(bore,stroke,con_rod,cr,180,0);
P_expansion = constant_k./(V_expansion).^gamma;
% find the value of t3 |
t3 = t4*cr^(gamma-1);
% state variables at state point 4
v4 = v1 ;
% p3v3^gamma = p4v4^gamma
p4 = p3*(v3/v4)^gamma ;
% therml efficiency of the engine
eff=1-(1/(cr).^(gamma-1));
figure(1)
hold on
plot (v1,p1,\'*\',\'color\',\'r\')
plot (V_compression,P_compression)
plot (v2,p2,\'*\',\'color\',\'r\')
plot (v3,p3,\'*\',\'color\',\'g\')
plot (V_expansion,P_expansion)
plot (v4,p4,\'*\',\'color\',\'g\')
2. thermal efficiency of the engine - 0.6299
REMARK : Also you should follow the format as we use to write a
report. Please don\'t just copy and paste the code. Use INSERT OPTION to insert a code.
Where is the plot and function ?
sorry i just forgot to put that.
3. FUNCTION-
function [V] = engine_otto(bore,stroke,con_rod,cr,start_crank,end_crank)
a = stroke/2;
R = con_rod/a;
v_swept = (pi/4)*bore^2*stroke;
v_clear = v_swept/(cr-1);
theta = linspace(start_crank,end_crank,100);
term1 = 0.5*(cr-1);
term2 = R+1-cosd(theta);
term3 = (R^2 - sind(theta).^2).^0.5;
V = (1+term1*(term2-term3)).*v_clear;
end
4. Graph-
every time when i am going to draw the line from p2 tp p3 and p4 to p1, the curve distorted. Thus i am not completing the graph